Babies with extremely low birth weights are at higher risk of developing psychiatric conditions in their adult life than those born with a healthy weight, new research has found.
A study in Canada of 84 people who were born with an extremely low birth weight (ELBW) - less than 1,000 grams – compared to 90 people born with a normal birth weight found they were twice as likely to have a clinically significant psychiatric disorder by the time they reached their thirties.
Those whose mothers had completed a full course of antenatal corticosteroids (ACS) – given to reduce the risk of morbidity and mortality in premature infants - were shown to be at an even higher risk of these conditions, in particular generalised anxiety disorder, generalised social phobia and inattentive attention deficit hyperactive disorder.
“The brains of people born preterm are marked by widespread alterations in regions known to be altered in those with psychiatric disorders”
Research on mental health of extremely low birth weight survivors in their 30s
The report states: “The brains of people born preterm are marked by widespread alterations in regions known to be altered in those with psychiatric disorders.
“Corticosteroids administered antenatally cross the placenta, and receptors for glucocorticoids are highly expressed in the limbic region…[This area] plays a vital role in the development of emotion, behaviour, and cognition and may be where ACS act to amplify brain changes present in survivors.”
It is already known that survivors of extremely low birth weight are at more risk of developing psychiatric problems in childhood and adolescence, but little research has been done to find out whether this continues into adulthood, note the study authors published in Pediatrics.
Previous research has shown that people who survive after having been born with very low birth weight – less than 1,500 grams – are by their twenties more likely to have mood disorders, anxiety and social problems.
But this study is the first to use the oldest cohort of survivors born with an extremely low birth weight.
The research also revealed this group was less likely to develop a substance or alcohol use disorder than those with a normal birthweight.
“This risk reduction may result from their cautious, shy, risk-avoidant personality style, higher parental monitoring earlier in life, or a later manifestation of their tendency to show lower levels of externalizing behaviour in childhood and adolescence,” adds the report.
The study authors conclude: “Future work is needed to replicate our ELBW and ACS survivors’ results in adulthood and to elucidate the psychosocial and biological pathways underlying our findings.”
They add: “Unfortunately, ELBW survivors who may benefit significantly from ACS at birth and in the neonatal period may be at an elevated risk of psychopathology in later life.
“However, it is important to stress that ACS is a lifesaving intervention, and even if our findings are replicated, we would advocate for close follow-up of these individuals rather than avoidance of ACS by women presenting with threatened preterm birth.”